Sheet metal container



April 11, 1944. I sc 2,346,619

SHEET METAL CONTAINER Filed May 8, 1942 Patented Apr. 11, 1944 N. Y., a cement o p ,IncL, New York; in of New Yo'rk l interestin ,1942; said N10: 445L235 zeta-s. (oi'zz'p' -sii The invention relates'to new and'useful improvements in a sheet metal container and more particularly to a sheet metal container of the type shown and described inpatents, Nos. 2,171,711 and 2,171,714 granted to' Walter G. Plumb et a1. and Herbert Schrader, respectively, onsep'temberfi, 1939.

Anobject of the invention is to provide a construction of side seam wherein the metal parts of the side seam in the region of the lap sections will be pres's'edirito intimate contact with a thermoplastic sealing material when the closure ends are secu'red'to the container body by'double seam- 1ng V A further object of the invention is to provide a lock and lap side seam-wherein one of the hooks of' th'e'lock section isextended tothe end of the side seam and becomes a part of the lap section.

Afurther object of the invention is to provide a side seam of theiabove type which'is rendered hermetically tight by a thermoplastic sealing niaterial which extends'thr'oughout the limits of the side seam, which sealing material is of such a character as to remain pliable and operates to close any leaksformed in the lap sectionsi during the Hanging or double seamingof the'ends thereto. i

These .and'other objects williin part be obvious and will in part be hereinafter more fully described; it 1 i in the drawing which shows by Wayoff illustration one embodiment of the invention, 4 V c Figure 1 is a plan view of a body-blank which has been notched and provided .withho'oks'Jpreparatory to the forming of acontainer'lb'odyy Figure 2 isan edge view'of the body blank shown in Figure 1; U y

. Figure 3 is aiview of a portion 'ofth container body in the region of the .sidevse'am after the seam has been bumpediandthe body initheregion' of the seam preflanged, said .view being taken from the outside of the containervbodmv i ;Eigure 4 is a section view on the line' 44 i wi. i t.

Figurejfiis a sectional view of the line 5-5 f i re t l Eigure 6 is, an inside ,viewota portion of the container body shown in Eigur.e 3;

Figure '1 is a v ca ec o a .t w.,thr ush the sidel seam i of the l containert bodyiatter the container body isbumped and ,pr'eflanged; 4

Figure .8 is avertical sectiqnal iewi througha portion of the side seam after the container'bo'dy has been flanged;

Figure 9 is a vertical sectional view througha potti'onof the side seam after the end closure'has beendo'u'ble seafnd theretol. v v.

Figure 10'isa'viewlshowing one way of applying the" thermoplastic sealing lmaterial tof vboth the inner' and outer facesfof the inside hook of the bodyblan'k. A

.iTheinvention is. directed. toilai-cohtainer ot. sheet metal and .of. the'type vwherein .thei body'iis usually r'eferredito .as a isolderless. side seam con-.4 ta'iner' body. Th'esideseam includes interlocking hooks and lapsectionsn .Theinside hook is extended-.to-theliullnlength oflthesideseamso that said hook 'exte'nds..out .iritofthdflarige and. is rolled into the. double seam joining i.an end closure to thebodyoi thecontainer. ,Theioutsideiho'ok terminates at thelowerl side o f..the' double seam whichisecuresthe end .closure to .Tthe Lbody'. During 7 the .burripingi...operation the. lap, section. at the end; of the outsidethookiis. pressed against the portion of. thelinside hook, which, extends throughout .the; lap. sectionand turn presses said hook tightly againstthe body. wall carrying themsame s lThisiorms three "walls in theilapsec-, v

tion ofithedseam. which areovery tightly brought into contact with each other. not onlyiduring the bumping operation,fb11t duringithe doubletseamingioperation which joins the ends of the container body, l s

Referring more-in detail to the drawing the body blank is indicated at I. This (body blank, is out along an inclined. line.2 at one end thereof which isiusually referred to. as a notchingsopera-I tion., The blank is folded back upon itself. at this notched end .to form, ahook\3 which is usually referredto asthe outside hook. ,The other end ofithe body blankis notlcut but is folded back upon itself .to form a .hook 4.which,extendsifrorri one side, ofthe ,blankto, the other and incthe, finishedside seam this :hook extends all the way from one end of the side seam to the other end Afterithe,bodyj-blank haslbeeni made upin the manner just describednthis insidehook .4 is.pre-. sented ..to.a,floatinsyrqll t tatinainabath f oat n ate iat a ato tar y a layer vor the coatin cm t ria Ihe hook .is, fiQQIFBQQtQdfiQ the coating roll that the at thermoplastictsealing materialmcarried by the roll will coat the hook n oth ides th re 1f \fop d. esirable,vv the, ou side lhookfit m y. b tcqat dontth c outside or onuboth sides with a thermoplastic sealing maiala t.

v ithe.7the l crrlor la 1 l, .mslmaterial is. o h a character'that'it remalnspliable even after the hook parts of the side seam will be brought into intimate contact with each other as shown in Figure 5. Either the bumping iron or the anvil horn on which the seam is bumped is preferably provided with projections which form indenta tions 6. The interlocked hook portions of the side seam are indicated at l in Figure 5. Along one side of the interlocked portions the body wall is bent inward, as indicated at 8, and along the other side of the hook portion of the side seam the body wall is provided with an outwardly extending bead'9 which places the metal of the bead closely around the base of the outside hook while the portion 8 of the body wall extends closely around the base of the inside hook. This draws the metal parts into very close intimate contact and causes the sealing material extendingthroughout the limits of the locked section to fillall the spaces and make a very efiicient hermetically sealed side seam section. This side seam, by the curving of the metal, is oifset outwardly from the body wall. The shaping of the body wall and the offsetting of the seam outwardly holds the hooks firmly interlocked and prevents any collapsing of the side seam due to external pressure applied to the body Wall.

The inside hook, as noted above, extends from one end of the side seam tothe other end thereof and the portion 4a of the inside hook will be bumped tightly against the body wall. The section H of the body wall extending beyond the outside hook overlaps the inside hook portion M as 'shown in Figure 4 and during thebumping operation the bumping iron will contact with this section I l forcing the same against the hook portion' 4a and bringing said hook portion into tight engagement with the bodywall.

As noted above, the inside hook 4 has coating material applied to both the inner. and outer faces thereof and therefore there will be coating materialbetween the hook section 4a and the body .wall carrying the same and between the hook section 4a and the body wall I I overlapping the same. This pressing of the body wall II and the hook portion do against the body wall carrying the hook portion will close the inner nook closely around the end of the outside hook 3 as indicated at I2 in Figure 7. This fills the space joining the hook section of the side seam' with the lap section of the side seam and makes a very tight hermetic seal for the side seam, not only in the hook section but in the lap section.

. During this bumping operation of the side seam the portion of the end of the container body Which is to be formed into a flange is bent radially outward for, what is referred to as a proflanging operation. In other words, these lapping sections in the region of the side seam are bent outwardly by a bumping operation which leaves them in tight contact because they are gripped between the anvil and the bumping iron during this preflanging operation. The bead-:9 is formed during the bumping operation as above noted and this bead vanishes in the portion of the body wall Whichis to be flanged. This bead takes up the stretch in the metal when the can body is preflanged, the side seam is not opened up as the bead supplies enough extra metal to take care of what is required for the flange.

After the can body has been bumped and preflanged in the manner described above, it is then subjected to a fianging die which will roll the edge portion of the body wall outward into a flange, as indicated at I 3 in Figure 8. During thi flanging operation the lap sections and the side seam, due to the initial shaping of the parts by the prefianging operation, will be carried out into the finished flange without breaking the seal between the lapsections. Here again the bead along the side seam which extends well out into the region which is flanged gives up slack to the forming of the flange and prevents lateral strainingon the lap sections of the side seam.

After the flange has been formed on the can body as shown in Figure 8, an end closure I4 is secured to the body by double seaming. This end closure has the usual depression providing-a vertical wall I5 in which depression the chuck of the seaming mechanism is placed. The flange it of the closure member I4 is rolled with theflange l3 into a double seam in the usual manner. This rolling of the parts into a double seam as shown in Figure 9 will press the outer lap section of the side seam against the extended portion of the inside hook and force the inside hook against the body wall carrying the same. It will also drawrthe inside hook tightly around the end of the outside hook and thus make a very tight seal, not only in the lap sections, but in that portion of the side seam where the lap sections join the interlocked hook sections. As noted above, the sealing composition is preferably of the thermoplastic type and is of such a character that it remains pliable so that the end closure, whenever it is secured to the container body, will aid in making a very tight side seam extending all the Way into the double seam.

It is obvious that many changes may be made in the details of construction of the solderless side seam sheet metal container described above without departing from the spirit of the invention asset forth in the appended claims.

I claim: 1 1. A sheet metal container comprising a body blankhaving its edge portions joined by a solderless side seam including an inner hook extending. the full length of the side seam and an outer hook terminating short of the ends of the side seam, said' hooks being interlocked throughout the length of the outer hook, the end portions of the inner hook being bent into contact with the body wall beyond the ends of the outer hook and lapped by the body wall carrying the outer hook and a plastic sealing composition covering theinner and outer faces of said inner hook and extending throughout the length of the lock and lap sections ofv the side seam for hermetically sealing the same.

2. A sheet metal container comprising a body blank having its edge portions joined by a solderless'side seam including an inner hook extending the full length of the side seam and an outer hook terminating short of the ends of the side seam, said hooks being interlocked throughout the length of the outer hook, the end portions of the inner hook being-bent into contact with the body wall beyond the ends of the outer hook and lapped by the body wall carrying the outer hook :and a plastic sealingcomposition covering the inner and outer iacesof said inner.

body, said inner hook being extended into said double seam and said outer hook terminating at the lower edge of the double seam whereby a. forming of the double seam will press the parts of the side seam beyond the end of the outer hook into intimate contact with each other and 5 the plastic sealing material therebetween.

HERBERT SCI-IRADER. 

